Intelligent stethoscope

Abstract

An intelligenet stethoscope for performing auscultation and for automatically diagnosing abnormalities based on body sounds is described in which the body sounds are received, digitized and stored in memory. The body sounds are recorded from a plurality of locations on the body, and all of the sounds are categorized according to specific characteristics to form a matrix of information. The generated matrix is then compared against a plurality of stored matrices using a technique similar to signature analysis. Each of the stored matrices contain information indicative of known abnormalities such as specific heart murmurs, lung abnormalities, etc. When a matrix match is found, the diagnosis is displayed on an LCD display formed in the body of the stethoscope. The LCD display is also capable of displaying a visual representation of the recorded body sounds. The resent invention is applicable to heart sounds, lung sounds, and bruits. A wide variety of heart and lung abnormalities along with their signatures are described and the specific steps required for the signature analysis is described.

What is claimed is: 
     
       1. An intelligent stethoscope for automatic diagnosis of sensed body sounds, comprising: (a) input means for receiving the sensed body sounds;   (b) first memory means connected to said input means for storing the sensed body sounds;   (c) second memory means for storing first characteristics of at least one representative body sounds corresponding to a known physical abnormality;   (d) control means connected to said first memory means and said second memory means for generating second characteristics corresponding to the sensed body sounds and for comparing said second characteristics corresponding to the sensed body sounds of said first memory means to said first characteristics of said at least one representative body sounds of said second memory means; and   (e) indicator means attached to said control means for indicating a match between said second characteristics and said first characteristics.   
     
     
       2. The stethoscope of claim 1 wherein said first memory means is further operable for storing said sensed body sounds in the form of digital data and wherein said second memory means is further operable for storing said at least one representative body sounds corresponding to a known physical abnormality is stored in said second memory means in the form of a matrix of characteristics. 
     
     
       3. The stethoscope of claim 1 wherein said indicator means further includes a display for indicating a diagnosis of said known physical abnormality corresponding to said match. 
     
     
       4. The stethoscope of claim 1 wherein said indicator means includes a display for displaying a visual representation of said body sounds of said first memory means. 
     
     
       5. The stethoscope of claim 1 wherein said first memory means is further operable for storing said sensed body sounds in said first memory means in the form of digital representations of analog waveform data. 
     
     
       6. An auscultation apparatus for automatically diagnosing abnormalities, comprising: (a) input means for receiving body sounds;   (b) digitizing means connected to said input means for digitizing said body sounds and for producing therefrom digitized body sounds;   (c) first memory means connected to said digitizing means for storing said digitized body sounds;   (d) second memory means for storing a plurality of matrices of characteristics each matrix corresponding to a known physical abnormality;   (e) control means connected to said first memory means and said second memory means for analyzing specific characteristics of said digitized body sounds, for building a generated matrix of characteristics therefrom and for comparing said generated matrix to each of said plurality of matrices of characteristics; and   (f) indicator means attached to said control means for indicating if a match between said generated matrix and at least one of said plurality of matrices of characteristics.   
     
     
       7. The apparatus according to claim 6 wherein said first memory means is further operable for storing said digitized body sounds in the form of a generated matrix of characteristics and wherein said control means is further operable for analyzing specific characteristics of said digitized body sounds by identifying waveform characteristics including amplitude, time intervals and frequency. 
     
     
       8. The apparatus according to claim 7 wherein said first memory means is further operable for generating said matrix of characteristics using a plurality of samples of body sounds taken at various locations on a patient's body. 
     
     
       9. The apparatus according to claim 6 wherein said indicator means includes a display for visually displaying a facsimile of said digitized body sounds stored in said first memory means. 
     
     
       10. The apparatus according to claim 6 wherein said indicator means further includes a display for indicating if a match was found and for indicating a diagnosis corresponding to one of said known physical abnormalities based on said match. 
     
     
       11. An auscultation apparatus for performing time-domain signature analysis, comprising: (a) input means for receiving body sounds;   (b) digitizing means connected to said input means for digitizing body sounds and for producing therefrom digitized body sounds;   (c) first memory means connected to said digitizing means for storing a plurality of said digitized body sounds;   (d) second memory means for storing a plurality of representative digitized body sounds corresponding to known physical ailments;   (e) third memory means for storing a software control program; and   (f) control means connected for controlling said input means, said digitizing means, said first memory means, said second memory means, and said third memory means, for executing said control program for causing the auscultation apparatus to perform the steps of: (i) receiving, digitizing and storing body sounds taken from at least one location on the body;   (ii) generating a matrix of data such that the entries in the matrix correspond to characteristics and attributes of the body sounds taken from at least one location on the body;   (iii) comparing the generated matrix from the body sounds to at least one matrix stored in said second memory means; and   (iv) indicating a match between said generated matrix and said at least one matrix stored in said second memory means.     
     
     
       12. The apparatus according to claim 11 wherein said first memory means, said second memory means and said third memory means all reside within the same physical package. 
     
     
       13. The apparatus according to claim 11 further including an indicator means attached to said control means for indicating said match between said generated matrix and said at least one matrix stored in second memory means. 
     
     
       14. The apparatus according to claim 13 wherein said control means further determines a diagnosis corresponding to one of said known physical ailments based on said match and said indicator means further indicates that diagnosis. 
     
     
       15. A method of automatically diagnosing abnormalities from body sounds comprising the steps of: (a) receiving from the body the audio sounds falling within the audible spectrum;   (b) digitizing the received body sounds and storing them in a memory;   (c) generating a matrix based on the characteristics and attributes of the stored digitized body sounds;   (d) comparing the generated matrix to at least one previously generated matrix corresponding to a known physical abnormality;   (e) indicating a match between said generated matrix and said stored matrix.   
     
     
       16. The method according to claim 15 further including the step of (f) displaying a diagnosis corresponding to the match of step (e) of said at least one previously generated matrix corresponding to a known physical abnormality. 
     
     
       17. The method according to claim 15 wherein said step (c) further includes the step of generating a matrix which is a serial collection of characteristics corresponding to attributes of the body sounds. 
     
     
       18. A continuous time-domain, visual display stethoscope, comprising: an acoustic bell adapted for receiving audible body sounds including a microphone for converting said body sounds into analog electrical signals;   analog-to-digital conversion means connected to said microphone for converting said analog body sounds into digital patterns on a real-time basis;   memory means connected to said conversion means for storing said digital patterns;   analysis means connected to said memory means for analyzing said digital patterns and for locating specific characteristics therein;   display means connected to said memory means and said analysis means for receiving said digital patterns and for displaying a time-domain, visual representation of said body sounds on time-magnitude axes and for displaying said specific characteristics; and   audio output means connected to said acoustic bell for passing to a listener said body sounds simultaneous with the time-domain display of said body sounds and said specific characteristics on said display means.   
     
     
       19. The stethoscope according to claim 18, wherein said analysis means further includes measurement means connected to said memory means and to said display means for measuring preselected time intervals of said digital patterns and for displaying the results of said measurements on said display means. 
     
     
       20. The stethoscope according to claim 18, wherein said analysis means further includes measurement means connected to said memory means and to said display means for locating and identifying the S1 and S2 heart sounds of a cardiac cycle, for measuring preselected magnitudes of said digital patterns, for displaying the location of the S1 and S2 heart sounds on said display means and for displaying the results of said measurements on said display means. 
     
     
       21. A visual display stethoscope, comprising: input means for receiving audible body sounds and for converting said body sounds into analog electrical signals;   analog-to-digital conversion means connected to said input means for converting said analog body sounds into digital patterns;   memory means connected to said conversion means for capturing a time interval of said body sounds and for storing said digital patterns corresponding to said time interval of said body sounds;   analysis means connected to said memory means for analyzing said digital patterns and for locating specific characteristics therein;   display means connected to said memory means and said analysis means for receiving said digital patterns and for displaying a frozen visual representation of said digital patterns on time-magnitude axes and for displaying and labeling said specific characteristics; and   display control means connected to said memory means and to said display means for controlling and manipulating the frozen visual representation of said digital patterns on said display means.   
     
     
       22. The stethoscope according to claim 21 wherein said display control means further includes means for expanding and contracting the time-axis representation of said digital patterns and wherein said analysis means is further operable for analyzing specific characteristics of said digital patterns by identifying waveform characteristics including amplitude, time intervals and frequency. 
     
     
       23. The stethoscope according to claim 21 wherein said display control means further includes means for panning the time-axis representation of said digital patterns to the left or right such that said time interval of said body sounds may be displayed which is greater than the capacity of the display means and wherein said analysis means is further operable for analyzing specific characteristics of said digital patterns by identifying and measuring time intervals between S1 and S2 heart sounds within said digital patterns. 
     
     
       24. An analytic visual display stethoscope, comprising: input means for receiving audible body sounds and for converting said body sounds into analog electrical signals;   analog-to-digital conversion means connected to said input means for converting said analog body sounds into digital patterns;   memory means connected to said conversion means for storing said digital patterns;   display means connected to said memory means for receiving said digital patterns and for displaying a visual representation of said digital patterns on time-magnitude axes; and   measurement means connected to said memory means and to said display means for automatically locating and measuring preselected features of said digital patterns and for automatically displaying the results of said measurements on said display means.   
     
     
       25. The stethoscope according to claim 24 wherein said measurement means further includes means for measuring the time interval between peak magnitude points on said digital patterns and for automatically displaying the results of said measurements on said display means. 
     
     
       26. The stethoscope according to claim 24 wherein said measurement means further includes means for measuring the peak magnitude of preselected points on said digital patterns and for automatically displaying the results of said measurements on said display means. 
     
     
       27. The stethoscope according to claim 24 wherein said measurement means further includes means for measuring the time interval between peak magnitude points on said digital patterns, for measuring the peak magnitude of preselected points on said digital patterns, for calculating therefrom the S1-to-S2 heart sound time interval and for automatically displaying said interval on said display means. 
     
     
       28. The stethoscope according to claim 27 wherein said measurement means further includes processor means for performing the steps of: (a) selecting a first time window on said digital patterns;   (b) locating the S1 heart sound by measuring the peak magnitude of all points on said digital patterns within said first time window and selecting the point with the largest magnitude;   (c) selecting a second time window on said digital patterns;   (d) locating the S2 heart sound by measuring the peak magnitude of all points on said digital patterns within said second time window and selecting the point with the largest magnitude;   (e) measuring the time interval between the S1 and S2 peak magnitude points on said digital patterns; and   (f) displaying said interval on said display means.   
     
     
       29. The stethoscope according to claim 28 wherein said processor means further performs the steps of: (g) comparing the results of said measurements and said time interval to preselected stored measurements and time intervals;   (h) performing a signature analysis based upon the comparison; and   (i) automatically diagnosing heart ailments based upon the results of the signature analysis.   
     
     
       30. A combination audio and visual stethoscope, comprising: an acoustic bell adapted for receiving audible body sounds;   a first tubular member connected to said acoustic bell;   a body connected to said first tubular member and including a visual display for displaying a visual representation of said body sounds on time-magnitude axes;   a second tubular member connected to said body;   at least one ear piece connected to said second tubular member for transmitting said audible body sounds for use by a listener; and   said body including: electronic input means attached within said acoustic bell for receiving said audible body sounds and for converting said body sounds into analog electrical signals;   analog-to-digital conversion means attached within said body and connected to said electronic input means for converting said analog body sounds into digital patterns;   memory means attached within said body and connected to said conversion means for storing said digital patterns;   said visual display being connected to said memory means for receiving said digital patterns and for displaying a visual representation of said body sounds on said time-magnitude axes; and   audio output means attached within said at least one ear piece for passing to a listener, said body sounds simultaneous with the real-time display of said body sounds on said display means.     
     
     
       31. The stethoscope according to claim 30, further including measurement means connected to said memory means and to said visual display for automatically measuring preselected features of said digital patterns and for automatically displaying the results of said measurements on said display means. 
     
     
       32. The stethoscope according to claim 31 wherein said measurement means is further operable for performing the steps of: (a) selecting a first time window on said digital patterns;   (b) locating the S1 heart sound by measuring the peak magnitude of all points on said digital patterns within said first time window and selecting the point with the largest magnitude;   (c) selecting a second time window on said digital patterns;   (d) locating the S2 heart sound by measuring the peak magnitude of all points on said digital patterns within said second time window and selecting the point with the largest magnitude;   (e) measuring the time interval between the S1 and S2 peak magnitude points on said digital patterns; and   (f) displaying said interval on said visual display.   
     
     
       33. The stethoscope according to claim 32 wherein said measurement means is further operable for performing the steps of: (g) comparing the results of said measurements and said time interval to preselected stored measurements and time intervals;   (h) performing a signature analysis based upon the comparison; and   (i) automatically diagnosing heart ailments based upon the results of the signature analysis.   
     
     
       34. The stethoscope according to claim 30, further including display control means connected to said memory means and to said visual display for controlling and manipulating the visual representation of said digital patterns on said display means.